In the air cargo industry, loaders are used to load cargo onto an aircraft and unload cargo from the aircraft. As used herein, therefore, the term “loader” is directed to apparatus for performing either or both of these functions. Generally, two types of apparatus of this type are in use. The first is a single platform loader which is elevated between a position adjacent the ground and a position at the height of the cargo door sill or lower edge. The second is a two platform loader in which a first platform is maintained at the level of the cargo door sill and a second platform is raised and lowered with respect to the first platform. Cargo to be unloaded from the aircraft is therefore transferred between the cargo compartment of the aircraft and the first platform and then transferred from the first platform to the second platform when the second platform is in its elevated position. The second platform is then lowered and the cargo is off-loaded. The loading procedure is reversed.
The current loaders have various drawbacks, especially with respect to accommodating larger aircraft being designed and manufactured today. For example, the cargo door of such larger aircraft is at a much higher level than in the past. Also, due to the larger size of the aircraft and correspondingly larger carrying capacities, much higher volumes of cargo must be loaded and off-loaded. Ideally, such loading and off-loading should be accomplished in a comparable amount of time to smaller aircraft. With current loaders, manufacturing a single, adjustable platform such that it can raise and lower to and from much greater heights presents practical problems related to stability and size requirements. In addition, the increased amount of required travel takes additional time, or increased speed, both of which may be undesirable.
For at least these reasons, it would be desirable to provide an aircraft loader capable of effectively handling the cargo loading and unloading needs of even the largest aircraft while maintaining low loading and unloading time requirements for loading and unloading the cargo.